Featured Research

from universities, journals, and other organizations

Small Earthquakes are Useful Predictor of Large Ones

Date:
December 5, 2007
Source:
Seismological Society of America
Summary:
Conventional wisdom in seismology says slip on faults that rupture during the largest continental strike-slip earthquakes is generally limited to the seismogenic layer, the upper 15 km or so of the earth's crust to which aftershocks extend and background seismicity is limited. That idea when coupled with theory predicts that the amount of slip on faults in large earthquakes should not continue to increase once the dimensions of a rupture have surpassed about 15 km. The prediction is not supported by observation.

Conventional wisdom in seismology says slip on faults that rupture during the largest continental strike-slip earthquakes is generally limited to the seismogenic layer, the upper 15 km or so of the earth's crust to which aftershocks extend and background seismicity is limited.

That idea when coupled with theory predicts that the amount of slip on faults in large earthquakes should not continue to increase once the dimensions of a rupture have surpassed about 15 km. The prediction is not supported by observation. Slip does continue to increase as the length of earthquake ruptures increase. The contradiction between the prediction and observation has long been recognized to suggest that the physics of large earthquakes is different than small.

This interpretation has been unsettling because it lends uncertainty to the idea that observations from small earthquakes, which are far more abundant, can be scaled upward to make predictions about much less frequent but far more damaging large earthquakes that will occur in the future, a common practice in seismology.

New work by seismologists Geoffrey C. P. King and Steven G. Wesnousky shows how the conundrum may be resolved if slip during the largest earthquakes is allowed to extend modestly below the seismogenic layer and that the base of the seismogenic layer is marked by a transition to stable sliding rather than viscous relaxation.

Geoffrey C. P. King is the Director of the Laboratoire Tectonique at the Centre Nationale de la Recherche Scientifique's Institut de Physique du Globe de Paris. Steven G. Wesnousky is Director of the Center for Neotectonic Studies and Department of Geological Sciences University of Nevada-Reno.

This research was published in the Bulletin of the Seismological Society of America.


Story Source:

The above story is based on materials provided by Seismological Society of America. Note: Materials may be edited for content and length.


Cite This Page:

Seismological Society of America. "Small Earthquakes are Useful Predictor of Large Ones." ScienceDaily. ScienceDaily, 5 December 2007. <www.sciencedaily.com/releases/2007/12/071204154741.htm>.
Seismological Society of America. (2007, December 5). Small Earthquakes are Useful Predictor of Large Ones. ScienceDaily. Retrieved September 1, 2014 from www.sciencedaily.com/releases/2007/12/071204154741.htm
Seismological Society of America. "Small Earthquakes are Useful Predictor of Large Ones." ScienceDaily. www.sciencedaily.com/releases/2007/12/071204154741.htm (accessed September 1, 2014).

Share This




More Earth & Climate News

Monday, September 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Lightning Hurts 3 on NYC Beach

Lightning Hurts 3 on NYC Beach

AP (Sep. 1, 2014) A lightning strike injured three people on a New York City beach on Sunday. The storms also delayed flights and interrupted play at the US Open tennis tournament. (Sept. 1) Video provided by AP
Powered by NewsLook.com
Thailand Totters Towards Waste Crisis

Thailand Totters Towards Waste Crisis

AFP (Sep. 1, 2014) Fears are mounting in Bangkok that poor planning and lax law enforcement are tipping Thailand towards a waste crisis. Duration: 01:21 Video provided by AFP
Powered by NewsLook.com
Washington Wildlife Center Goes Nuts Over Baby Squirrels

Washington Wildlife Center Goes Nuts Over Baby Squirrels

Reuters - US Online Video (Aug. 30, 2014) An animal rescue in Washington state receives an influx of orphaned squirrels, keeping workers busy as they nurse them back to health. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Raw: Volcano Erupts on Papua New Guinea

Raw: Volcano Erupts on Papua New Guinea

AP (Aug. 29, 2014) Several communities were evacuated and some international flights were diverted on Friday after one of the most active volcanos in the region erupts. (Aug. 29) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins